@lpgroup/feathers-counters-service NPM

@lpgroup/feathers-counters-service

Feathersjs hook that adds a counter key to data or result.

The package consists of the service counters and the hook counter. The hook will store the number of times a specific event has occured in a database through the service.

This funcionality can for example be used for statistics purpose. Counting the number of times GET has occured on a specific endpoint. Number of times a specific user has accessed a service. It can also be used to calculate a unique customer number on a customer endpoint on a specific organisation.

Install

Installation of the npm

npm install @lpgroup/feathers-counters-service
// or
yarn add @lpgroup/feathers-counters-service

The hook

before	after	methods	multi	source
yes	yes	all	yes	source

arguments

property	type	default	description
`format`	`string`	required	A format that makes the counter unique
`periodFmt`	`string`	required	The date period that the counter is counting. https://date-fns.org/v2.28.0/docs/format
`key`	`string`	true	The name of the key in the returned json data/result
`step`	`number`	1	Number of steps to increase the counter each time, postive or negative.
`description`	`string`	null	Description of the counter

The service

The service is required by the hook. To install it, modify feathers service file, app-ng/src/services/index.js, add the follwoing.

import { counters } from "@lpgroup/feathers-counters-service";

export default (app) => {
  /* ... */
  app.configure(counters);
};

Endpoints

POST: /counters
GET: /counters
GET: /counters/:alias
PATCH: /counters/:alias
PUT: /counters/:alias
DELETE: /counters/:alias

Object

{
  "alias": "status-visits-2021-11",
  "group": "status-visits",
  "period": "2021-11",
  "value": 50,
  "description": "status-visits"
  /* commonAttributes */
}

Example 1

Give each customer on an organisation a unique customer number, on the endpoint /organisations/:organisationAlias/customer.

The before hook will add the key customerNumber to data and store it in the database handled by the endpoint.

{organisationAlias} comes internally from the url in params.query.

import { counter } from "@lpgroup/feathers-counters-service";

export default {
  before: {
    all: [],
    find: [],
    get: [],
    create: [
      counter("{organisationAlias}-visitors", null, "customerNumber", 1, "Latest customerNumber"),
    ],
    update: [],
    patch: [],
    remove: [],
  },
};

Example 2

Calculate the number of times a user has accessed the GET method on /status?user=admin.

{user} comes internally from the query parameter in params.query.

import { counter } from "@lpgroup/feathers-counters-service";

export default {
  after: {
    all: [],
    find: [],
    get: [
      counter(
        "total_gets-{user}",
        null,
        "userAccesses",
        1,
        "Total number of calls done by a specific user",
      ),
    ],
    create: [],
    update: [],
    patch: [],
    remove: [],
  },
};

Example 3

Calculate number of calls during a month.

The counter will start from the beginning again every month. The statistics for earlier months will be stored in the /counters service.

import { counter } from "@lpgroup/feathers-counters-service";

export default {
  after: {
    all: [],
    find: [],
    get: [],
    create: [counter("visitors", "yyyy-MM", "visits", 1, "Number of visits during a month")],
    update: [],
    patch: [],
    remove: [],
  },
};

Example 4

Keep track of a stack of files, and for every create will increase 1 and for every delete will decrease 1.

import { counter } from "@lpgroup/feathers-counters-service";

export default {
  after: {
    all: [],
    find: [],
    get: [],
    create: [counter("files", null, "files", 1, "Total number of files")],
    update: [],
    patch: [],
    remove: [counter("files", null, "files", -1, "Total number of files")],
  },
};